Photographs of post-exam student pranks posted on the social networking website Facebook are being used by Oxford University authorities to discipline those involved, warns the university?s student union.

Oxford University Student Union warns on its website: ?It has been brought to the attention of the Student Union that the Proctors [university disciplinary staff] have been using evidence gathered by Facebook for disciplinary matters. Specifically, photos from Post-Exam Celebrations on Merton Street have been sent to members of the University (including those already finished) as evidence of their being involved in trashings.?

Such ?trashing? activities can involve covering fellow students with confetti, flour or champagne and students who break university rules are believed to face a possible fine.

Among those reported to have been hit is Alex Hill, a maths and philosophy student who is understood to have received an email from university authorities stating that three images show her engaged in ?disorderly conduct?.

She told today?s Times newspaper: ?I don?t know how the proctors got access to it. I thought my privacy settings were such that only students could see my pictures.?

One of the images shows her with a fellow student covered in foam.

The union urges students to alter their Facebook account privacy settings to prevent university staff viewing profiles and photographs.

The union’s website (pictured) adds: ?While the Student Union does not condone unruly, violent or disorderly behaviour, we believe that the privacy of our members should be protected and that disciplinary procedures at all levels within the University should be fair and transparent.?

At the time of writing, Amateur Photographer magazine was awaiting comment on the matter from Oxford University and Facebook.